/**
 * ***************************************************************************** Copyright (c) 2000,
 * 2006 IBM Corporation and others. All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0 which accompanies this
 * distribution, and is available at http://www.eclipse.org/legal/epl-v10.html
 *
 * <p>Contributors: IBM Corporation - initial API and implementation
 * *****************************************************************************
 */
package org.eclipse.search.internal.core.text;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;

/** Adapting a document to a CharSequence */
public class DocumentCharSequence implements CharSequence {

  private final IDocument fDocument;

  /** @param document The document to wrap */
  public DocumentCharSequence(IDocument document) {
    fDocument = document;
  }

  /* (non-Javadoc)
   * @see java.lang.CharSequence#length()
   */
  public int length() {
    return fDocument.getLength();
  }

  /* (non-Javadoc)
   * @see java.lang.CharSequence#charAt(int)
   */
  public char charAt(int index) {
    try {
      return fDocument.getChar(index);
    } catch (BadLocationException e) {
      throw new IndexOutOfBoundsException();
    }
  }

  /* (non-Javadoc)
   * @see java.lang.CharSequence#subSequence(int, int)
   */
  public CharSequence subSequence(int start, int end) {
    try {
      return fDocument.get(start, end - start);
    } catch (BadLocationException e) {
      throw new IndexOutOfBoundsException();
    }
  }
}
